Huki has been inactive lately, so he can't help – he's the best person that can help with technical stuff.

What I can say is that right now RVGL can read files only if they are stored in the internal memory of the mobile device. You can't install RVGL or put RVGL files in your external SD card in your phone, RVGL won't read it nor find it, RVGL won't work.